Department of Energy Science and Technology, Environmental Waste Recycle Institute, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
Department of Energy Science and Technology, Environmental Waste Recycle Institute, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
Environ Pollut. 2021 Nov 1;288:117717. doi: 10.1016/j.envpol.2021.117717. Epub 2021 Jul 7.
Direct utilization of waste polyethylene terephthalate (PET) from the environment to form highly porous aerogel technology for oil absorption is an attractive approach from the view point of green chemistry. However, the oil absorption reaction is limited by low oil absorption capacity and less stability. For now, silica aerogel are used to solve these problem. Our goal is to substitute to these silica aerogel with PET aerogel technology. Herein, we have prepared an environmental waste PET based aerogel with 1.0:0.5 wt% PET, polyvinyl alcohol (PVA), and glutaraldehyde (GA) 0.2% v/v were dispersed in 10 mL DI water, followed by homogenization (30 min), sonication (10 min), and ageing (2 h) at 70 °C. To escape macroscopic cracking, cooling (8 h) at 4 °C was followed by freezing (6 h), freeze drying at -80 °C, and 5 mTorr for 18 h. The hybrid PET aerogel displays excellent performance towards oil absorption. Notably it showed high absorption capacity towards the different oils about 21-40 times its own weight, depending on the viscosity and density of the oil and solvents within 15-35 s, 25 °C, and 2 × 2 cm aerogel size. In addition, the aerogel shows there is no change in structure after several recycles due to high mechanical strength. Furthermore, because of the PET aerogel's high porosity (99.74%) and low density (0.0311 g/cm), close bonding between PET-PVA occurs. Therefore, aerogel shows hydrophobic nature, good mechanical strength, high thermal stability, arrangement of the interconnected fibrillar pore network offers a high surface to volume ratio, low surface energy, high surface roughness, and more reusability. All these parameters are responsible for high oil absorption.
从绿色化学的角度来看，直接利用环境中的废聚对苯二甲酸乙二醇酯（PET）形成高多孔气凝胶技术来吸收油是一种很有吸引力的方法。然而，吸油反应受到低吸油能力和低稳定性的限制。目前，使用硅气凝胶来解决这些问题。我们的目标是用 PET 气凝胶技术来替代这些硅气凝胶。在这里，我们已经用 1.0:0.5wt%的 PET、聚乙烯醇（PVA）和戊二醛（GA）0.2%v/v 制备了一种环境废 PET 基气凝胶，将其分散在 10ml DI 水中，然后进行均化（30min）、超声（10min）和在 70°C 下老化（2h）。为了避免宏观开裂，然后在 4°C 下冷却（8h），接着冷冻（6h），在-80°C 下冷冻干燥，并在 5mTorr 下干燥 18h。该混合 PET 气凝胶在吸油方面表现出优异的性能。值得注意的是，它对不同油的吸收能力很高，大约是其自身重量的 21-40 倍，这取决于油和溶剂的粘度和密度，在 25°C 下，2×2cm 气凝胶尺寸下，吸收时间为 15-35s。此外，由于机械强度高，气凝胶在多次回收后结构没有变化。此外，由于 PET 气凝胶的高孔隙率（99.74%）和低密度（0.0311g/cm），PET-PVA 之间发生紧密结合。因此，气凝胶具有疏水性、良好的机械强度、高热稳定性、互连纤维状孔网络的排列提供了高的比表面积与体积比、低表面能、高表面粗糙度和更高的可重复使用性。所有这些参数都有助于高吸油能力。
